I don't think it was "broken" to brute force one of four options, but I've updated it to minimize brute force. You might enjoy viewing the source code of the HTML to read the entire walkthrough at once. There's now just a few instances of brute forcing (one of two possibilities, never one of four).
Jr qba'g arrq gb jnvg nf yngr nf 21-YV gb svaq 02-YV. 08-RQ yvaxf gb 03-NG, juvpu yvaxf gb 02-NG, juvpu cebirf gung Gbal jnfa'g va gur Yvivat ebbz, tvivat hf 02-YV. Sebz gur svefg thrffrq svyr 04-FG, V guvax gur cngu gb 02-YV vf: 05-QV, 06-FG, 04-OV, 03-XV, 01-OV, 05-XV, 06-RQ, 07-RQ, 08-RQ, 03-NG, 02-NG.